[kmill]

By "random first file" you mean "first file in the directory," which is for the cli. The printBasis function is the driver for the P part of the REPL, and it's not exactly something that the interpreter depends on for correctness. Poking around the codebase, it looks like they could give types fairly easily to this function, but they just haven't done it yet.

It looks to me like you found one of the only functions that use 'any' in the entire codebase. Others are things involving bindings in an environment (where anything really can appear, though one might argue a union type restricting to only ML value types would be more appropriate) or generic functions like for equality testing, which I'm not sure exactly why they take 'any'.